Liquid fuel backpacking stove

ABSTRACT

A stove ( 20 ) having a burner bottom ( 34 ) with an integrated trough ( 46 ) for catching fuel. The trough ( 46 ) may be formed, for example, by a section that is captured between a raised center ( 44 ) of the burner bottom ( 34 ) and a raised outer annular rim ( 42 ) of the burner bottom. A burner top ( 36 ) for the stove ( 20 ) includes a plate ( 38 ) that directs fuel contacting the burner top down into the trough ( 46 ) in the burner bottom ( 34 ). This plate ( 38 ) may be, for example, a plate having a downward-turned outer annular lip ( 39 ) that extends toward the trough ( 46 ). A fuel tip ( 50 ) is provided that extends down into a liquid fuel tank ( 26 ) for the stove ( 20 ). The fuel tip ( 50 ) includes a piston ( 58 ) that is moveable to provide a lean fuel, air-fuel mixture upon start of the stove, and a rich fuel, air-fuel mixture after the stove is started.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application Ser. No. 60/727,517, filed Oct. 17, 2005, and U.S. provisional application Ser. No. 60/762,615, filed Jan. 27, 2006, both of which are incorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to liquid fuel burner appliances, and more specifically to backpacking and camping stoves.

BACKGROUND OF THE INVENTION

Liquid fuel camp stoves and lanterns for camping and outdoor use are well known and are described, for example, in U.S. Pat. No. 3,876,364, which is owned by The Coleman Company, Inc., assignee of the present invention. Liquid fuel which is used in such camp stoves and lanterns may be, for example, COLEMAN brand fuel, white gas, unleaded gasoline, or other liquid fuels.

In conventional liquid fuel camp stoves such as the ones which The Coleman Company, Inc. has offered for many years, fuel is contained in a pressure vessel or fuel tank into which air is pumped under pressure. As described in U.S. Pat. No. 3,876,364, the fuel tank is equipped with a dip tube which extends to nearly the bottom of the tank. The dip tube is closed at the bottom with the exception of a small diameter orifice through which fuel is allowed to enter. The dip tube has an internal conduit which is open at the bottom and which communicates with the upper part of the pressure vessel above the maximum intended fuel level. The dip tube orifice can be partly blocked by insertion of a needle which is suitably connected to the fuel control system. The needle partly blocks the orifice during the lighting cycle and is removed to leave the orifice unblocked during the normal burn cycle. This partial blockage during the lighting cycle causes air to be drawn down the space between the internal and outer conduits of the dip tube from an opening at the upper part of the pressure vessel. As this air accompanies fuel up the internal conduit, a fuel-lean mixture of fuel and air is created to enhance lighting. A fuel-lean mixture is needed at initial lighting, because the fuel in the mixture is not vaporized and thus must be mixed with a lot of air for combustion. The air-fuel mixture then passes to a generator which is connected to the dip tube by the fuel control system. The generator is a metal tube which passes above the burner of the stove into a venturi assembly which is connected to the burner. The generator is heated by the flame of the burner when the burner is operating. Fuel is discharged at high velocity from an orifice or jet at the end of the generator into the venturi where air is aspirated and mixed and fed to the burner with the air/fuel mixture as a combustible mixture for burning.

After the burner has been operating for an initial period and the generator is sufficiently heated, the fuel that travels through the generator is vaporized. As such, after the generator is heated, the fuel expands and may be supplied in a less lean mixture. At this point, the needle may be removed from blocking of the passage.

In U.S. Pat. No. 3,876,364, the restricting needle is operated by rotating a fuel control knob. In other appliances, a lever is used to adjust the appliance for starting and running. The lever is moved up to start and then down to run.

The foregoing structure for allowing liquid fuel appliances to be lighted when the generator is cold is referred to as an “instant lighting system.” Liquid fuel appliances which do not include an instant lighting system require some other means for heating the generator during start-up, for example, liquid priming fuel, or heating paste. In either event, the lighting process is difficult for a user. Often, a user will forget to switch the needle (e.g., by moving the lever) after the lighting process. If liquid priming fuel is used, then the process can often take a minute or more, and results in blackening of the bottom of the stove.

SUMMARY OF THE INVENTION

The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later.

In accordance with an embodiment, a stove is provided having a burner bottom with an integrated trough for catching fuel during a burner lighting stage. The trough may be formed, for example, by a section that is captured between a raised center of the burner bottom and a raised outer annular rim of the burner bottom.

In accordance with another embodiment, a burner top for the stove includes a plate that directs fuel contacting the burner top down into the trough in the burner bottom. This plate may be, for example, a plate having a downward-turned outer annular lip that extends toward the trough.

In accordance with another embodiment, a fuel tip is provided that extends down into a liquid fuel tank for the stove. The fuel tip includes a piston that is moveable to provide a lean air to fuel mixture upon start of the stove, and a less lean air to fuel mixture after the stove is started.

In accordance with another embodiment, a stove is provided that includes an enclosed pan spaced from a burner. A tube or other conduit extends between the enclosed pan and the burner. A generator feeds into the enclosed pan. A venturi tube may be connected between the closed pan and the generator. The closed pan serves as a reservoir for fuel at a starting of the stove. The pan is heated by the generator so that fuel evaporates and is burned at the burner.

Other features of the invention will become apparent from the following detailed description when taken in conjunction with the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side perspective view of a stove in accordance with an embodiment of the invention;

FIG. 2 is an exploded side perspective view of a burner assembly for the stove in FIG. 1;

FIG. 3 is a side perspective view of a burner bottom for the burner assembly in FIG. 2;

FIG. 4 is a sectional view of the burner assembly of FIG. 2;

FIG. 5 is top view of a fuel tip and air inlet tube for use with the stove of FIG. 1 in accordance with an embodiment;

FIG. 6 is an exploded side perspective view of the fuel tip of FIG. 5;

FIG. 7 is a cross sectional view of the fuel tip of FIG. 5, with a piston in a stove-operating position in accordance with an embodiment;

FIG. 8 is a cross sectional view of the fuel tip of FIG. 5, with a piston in a stove-starting position in accordance with an embodiment;

FIG. 9 is a dual burner stove in accordance with an embodiment of the invention;

FIG. 10 is an alternate embodiment of a piston for use with the fuel tip of FIG. 5 in accordance with an embodiment; and

FIG. 11 is an alternate embodiment of a stove.

DETAILED DESCRIPTION

In the following description, various embodiments of the present invention will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to one skilled in the art that the present invention may be practiced without the specific details. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described.

Referring now to the drawings, in which like reference numerals represent like parts throughout the several views, FIG. 1 shows a backpacking stove 20 in accordance with an embodiment of the invention. In the embodiment show, the backpacking stove 20 includes a mushroom-shaped burner 22 connected by a fuel feed line 24 to a liquid fuel tank 26. The liquid fuel feed line 24 connects to a cleaning needle control valve 27 which in turn is connected to a generator 28. The generator 28, in a manner known in the art, winds around and over the mushroom-shaped burner 22 so that it may be heated by a flame coming out of the burner. The generator 28 then extends downward to a bottom of the stove 20 and upward in a vertical direction (FIG. 4) into the bottom of the mushroom-shaped burner 22.

As can be seen in FIG. 2, a lower heat shield 30 (removed in FIG. 4 so as to show detail) is positioned below the mushroom-shaped burner 22. A burner bushing 32, which serves as a venturi for the backpacking stove 20, extends upward through the center of the heat shield 30. The burner bushing 32 extends slightly through an opening in a burner bottom 34 which is aligned just above the heat shield 30. A burner top 36 is positioned over the burner bottom 34.

In accordance with an embodiment, a plate 38 (FIG. 4) having a downwardly turned circumferential outer lip 39 is centered on a bottom side of the burner top 36 and arranged so that the downwardly turned circumferential outer lip 39 extends downward. The plate 38 is connected to or formed integral with the burner top 36. Alternatively, the lip 39 may be formed in the bottom of the burner top 36 without the use of a plate structure.

Turning now to FIG. 3, the burner bottom 34 in the embodiment shown in the drawings includes an outer rim 40. An annular ridge 42 is positioned just inside of the outer rim. The burner bottom 34 also includes a raised center 44. A trough 46 is formed between the annular ridge 42 and the raised center 44. In an embodiment, the downwardly turned circumferential outer lip 39 is arranged so that the lip 39 is directed downward toward the trough 46. The purpose of this arrangement is described below.

Referring now to FIG. 5, a fuel tip 50 is provided in accordance with an embodiment of the invention. In the embodiment shown in FIG. 5, the fuel tip 50 is attached to an air inlet tube 52, an end of which is, in a manner known in the art, positioned above the fuel level in the liquid fuel tank 26 when the liquid fuel tank is full.

An exploded perspective view of the fuel tip 50 is shown in FIG. 6. As can be seen, the fuel tip 50 includes a body 54 and a plug 56 that is threaded into one end of the body 54. A piston 58 floats within the body 54, as further described below. A spring 60 is positioned to bias the piston 58 toward the plug 56.

As can be seen in FIG. 7, the body 54 includes a center bore 62. A threaded fuel end 64 is positioned on one end of the center bore 62, and an outlet 66 is positioned on the opposite end. An air inlet 68 is positioned between the threaded fuel end 64 and the outlet 66, and enters the bore 62 perpendicular to a longitudinal axis of the bore. The air inlet 68 is attached to the air inlet tube 52. Similarly, the outlet 66 is connected to a conduit 70 (FIG. 1) that provides an air and fuel mixture to the fuel feed line 24, as is further described below.

The plug 56 threads into the threaded fuel end 54. A rear slot 72 is provided on the back of the plug 56 as a tool receiving pattern, for example to receive the end of a screw driver. A different pattern may be used. A front slot 74 is positioned on the opposite end of the plug. The plug 56 includes a bore 76 that extends through its center. The bore includes a narrow opening 78 positioned toward the front (right side in FIG. 7) of the bore 76.

The piston 58 includes a front slot 80. A narrowed portion 81 is formed on the front of the piston 58 so that a shoulder 82 is formed. The spring 60 extends over the narrowed portion 81 and against the shoulder 82. A stem 84 extends off the rear portion of the piston 58. The stem 84 includes a narrow portion 86 at the forward end, and a wider portion 88 at the rearward end.

The stem 84 and the piston 58 are arranged and configured so that the piston 58 may move longitudinally in the bore 62 of the body 54. During this movement, the stem 84 moves along the narrow opening 78 of the plug 56.

As is known, a stove burner, such as the mushroom-shaped burner 22, needs far more air than fuel at start up for aspiration of the burner. However, typically, upon start up, the fuel line, such as the fuel feed line 24, is full of fuel, causing the initial stream from the fuel feed line to be much too rich in fuel. As described below, the backpacking stove 20 includes both the trough 46 in the burner bottom 34 and the novel fuel tip 50 to address this problem.

In operation, the air in the liquid fuel tank 26 is pressurized, for example by manual pumping of a pump 90 (FIG. 1) in a manner known in the art. This pressurized air (A in FIG. 1) is in fluid communication with the air inlet tube 52, and therefore the air inlet 68 of the body 54 of the fuel tip 50. Air enters the fuel tip 50 through this air inlet 68. The back of the plug 56 is in communication with the liquid fuel (F in FIG. 1) in the tank, and fuel flows into the fuel tip 50 through the bore 76 in the plug 56.

At starting of the burner 22, there is no back pressure in the fuel feed line 24, and thus air pressure from the liquid fuel tank 26 extends through the air inlet 68 and pushes against the back side of the piston 58. This causes the piston 58 to move to the right against the pressure of the spring 60, such as to the position shown in FIG. 8. At this position, the wider portion 88 of the stem 84 of the piston 58 is aligned with and received within the narrow opening 78 in the plug 56. Thus, the wider portion 88 of the stem 84 effectively closes most of the narrow opening 78, limiting the fuel flow into the center bore 62 of the body 54. The gap between the inner walls of the narrow opening 78 and the outer surface of the wider portion 88 of the stem 84 may be sized appropriately so as to give the appropriate fuel intake when the piston 58 is in this position.

In accordance with an embodiment, when the piston 58 is in the position in FIG. 8, the spring 60 is fully compressed. Thus, the flow of air and fuel around the piston 58 and through the spring 60 is limited, or may be blocked altogether. For this reason, the front slot 80 is provided on the front of the piston 58. An air-fuel mixture may flow into the front slot 80 and through the center of the compressed spring 60, and may easily arrive at and flow out of the outlet 66.

Because the wider portion 88 of the stem 84 is positioned in the narrow opening 78, the air-fuel mixture that flows to the outlet 66 is very lean. This mixture provided with the wider portion 88 of the stem 84 positioned in the narrow opening 78 is referred to herein as the “start position” fuel mixture.

On initial starting of the backpacking stove 20, a user pumps the pump 90 to pressurize the fuel tank 26, turns on the fuel, for example via a valve on the fuel tank (not shown, but known) and lights the mushroom-shaped burner 22. Although a very lean fuel mixture is provided by the fuel tip when the fuel tip is in the start position, as described above, there may be a significant amount of fuel in the liquid fuel feed line 24, causing a very fuel rich mixture to first reach the mushroom-shaped burner 22. When the valve on the fuel tank is opened, fuel that is already in the line 24 is forced through the fuel feed line 24 and the generator 28 by the air pressure from the liquid fuel tank 56. The quantity of fuel in the line may be minimized by having an obstruction in the line, such as a rubber rod. As the fuel flows rapidly through the generator 28, and through the burner bushing 32, the fuel hits the plate 38.

The fuel flows across the plate 38 and outward to the downwardly-turned circumferential outer lip 39. The fuel then drips downward off the downwardly-turned circumferential outer lip 39 into the trough 46.

Some of the fuel is ignited as it enters the mushroom-shaped burner 22, and that lit fuel aids in starting of the backpacking stove 20. This initial flame aids in heating of the generator 28.

Heating of the generator 28 causes vaporization of fuel in the generator. As the fuel is vaporized, the fuel takes more volume in the generator 28, and back pressure in the fuel feed line 24 and at the outlet 66 is increased. As this back pressure increases, the pressure equalizes across the piston 58, and the spring 60 drives the piston backward to the position shown in FIG. 7. In this position, the narrow portion 86 of the stem 84 is aligned with the narrow opening 78 of the plug 56, and fuel flow through the plug 56 and around the stem 58 is increased. When the piston 58 is to the left as is shown in FIG. 7, the rear portion of the piston engages or is closely situated near the front portion of the plug 56. Thus, it is possible that the piston 58 may block fuel flow through the plug. To allow free fuel flow, the front slot 74 permits fuel to flow through the narrow opening 78, out through the slot, and around the piston 58.

The narrow portion 86 may be sized appropriately so that this fuel flow may be at a desired rate. The increase in fuel flow results in a richer air-fuel mixture which is fed to the outlet 66 and the fuel feed line 24 during normal operation of the backpacking stove 20.

After the generator 28 is heated and is operating, the fuel within the trough 46 is vaporized by heating of the burner 22 through the flame. Eventually, all fuel is evaporated out of the trough 46, and combustion occurs only from fuel fed through the fuel feed line 24. At this point, the backpacking stove 20 is running at normal operating fuel flow.

The unique fuel tip 50 provides a number of benefits. First, the air-fuel mixture is automatically adjusted as a result of back pressure provided by the generator 28. Therefore, unlike in prior art devices, the user does not have to operate a needle or lever or otherwise manually change operation of the backpacking stove 20 after the initial start of the backpacking stove. In addition, the fuel tip 50 may adjust according to conditions. As an example, during windy conditions, the flame may be blown out of direct contact with the generator 28, so that the generator is no longer adequately heated for vaporization of the fuel. In such a situation, in many prior art stoves, the fuel mixture, because it is no longer vaporized, is too rich, and excess fuel is provided at the burner. A lean fuel mixture must be supplied for recovery, usually by using the starting process, such as the flipping of a lever.

In contrast, if the generator 28 of the present invention is no longer adequately heated, then back pressure drops and the piston 58 is free to move back to the position shown in FIG. 8. The starting process then may continue with the lean fuel mixture until the generator is again heated to the proper level so that back pressure is sufficient to move the piston back to the position shown in FIG. 7.

As can be understood, the piston 58 moves to the position shown in FIG. 8 when the air pressure on the back of the piston exceeds the biasing force of the spring 60 and the back pressure from the fuel line 24. On the other hand, the piston 58 moves to the position shown in FIG. 7 when the back pressure from the fuel line 24 and the biasing force of the spring 60 exceeds the air pressure on the back of the piston from the air inlet 68.

A person of ordinary skill may select the spring constant of the spring 60 and may properly arrange the piston 58 so as to provide desired operation of the fuel tip 50. The fuel tip 50 may be rearranged along with the piston 58 so that operation may be performed without biasing of the spring 60, for example by providing a free floating piston. In addition, the center bore 62 may be rearranged relative to the piston 58 to provide different pressures against the piston.

In an embodiment, air pressure within the fuel tank 26 is typically at 23 pounds per square inch. During optimal operation of the stove 20, the back pressure within the fuel line 24 is slightly less than that amount; for example, the back pressure may be 22 pounds per square inch.

As can be understood, the amount of back pressure in the fuel line 24 that is needed to move the piston 58 to the position in FIG. 7 is variable based upon the amount of air pressure in the tank 26. That is, if the tank is pumped to a higher pressure, more back pressure is needed to move the piston 58 to the position shown in FIG. 7. However, at initial lighting of the stove 20, the back pressure is minimal, and thus the piston is moved to the position in FIG. 8. As the stove gets hotter and back pressure increases, the back pressure eventually is high enough to, along with the spring 60, overcome the pressure differential to move the piston 58 to the position shown in FIG. 7.

In accordance with another embodiment shown in FIG. 10, an o-ring 98 (FIG. 10) may be provided on the stem side of the piston 58. This o-ring 98 acts as a bumper for the piston 58 when the piston moves to the closed position shown in FIG. 7. As such, any clicking noise that may be generated by the piston 58 moving against the inside of the valve body may be reduced or eliminated by the cushioning effect of the o-ring 98.

FIG. 9 shows a double burner stove 100 in accordance with an embodiment of the invention. The double burner stove 100 includes a fuel feed line 102, similar to the fuel feed line 24, but leading to a fuel manifold 104. Valves 106, 108 are provided on opposite sides of the manifold 104 for feeding fuel to separate fuel lines 110, 112 on opposite sides of the manifold 104. These fuel lines feed two separate burners 114, 116.

The fuel tip 50 of the invention permits the double burner stove 100 to be operated. Without such a fuel tip, an attempt to light one of the burners 114, 116 after the other burner is already operating would result in an overly lean air-fuel mixture at the already running burner and most likely would cause it to go out. The fuel tip 50 permits automatic adjustment for such a situation so that air-fuel mixtures for each of the burners 114, 116 are maintained as needed. Also, air does not continuously move through the line, which would require continuous pumping.

As an example, if the burner 114 is operating, and the burner 116 is lit, the lack of fuel pressure by the generator for the burner 116 causes the fuel tip 50 to move to the starting position and provide a fuel lean mixture. After the burner 116 is operating, the fuel tip 50 returns to the operating position. The fuel tip 50 operates as described above when a first of the two burners 114, 116 is lit, or both burners are lit at the same time.

FIG. 11 shows an alternate embodiment of a stove 200. The stove 200 includes a generator 202, similar to the generator 28. However, instead of feeding into the bottom of the burner, the generator 202 feeds to a downward facing venturi tube 204. The venturi tube 204, in turn, is attached to the top of an enclosed pan 206. An upwardly extending burner tube 208 extends from an opposite side of the enclosed pan 206 to a burner 210.

The arrangement of the stove 200 shown in FIG. 11 is advantageous in that the enclosed pan 206 provides a location for fuel to accumulate at the beginning of a starting process. In addition, the length of the burner tube 208 spaces this fuel from combustion in the burner 210, and thus the fuel within the enclosed pan 206 is not used as part of the initial burning process.

Upon initial lighting of the stove 200, the fuel that is within the fuel line to the stove (described above) is directed through the venturi tube 204 downward into the enclosed pan 206. This fuel accumulates in the pan 206, with some fuel mixing with air to flow upward through the burner tube 208 into the burner 210. This fuel and air mixture is lit by the user and is typically much leaner than a fuel and air mixture at initial start up, because much of the liquid fuel is maintained within the enclosed pan 206.

Because the mixture of fuel and air is leaner, the flame from the burner 210 is much hotter, providing faster heating of the generator 202. The generator 202 then works in conjunction with the fuel tip 50 to provide adequate fuel to the burner 210.

As the generator 202 is heated, the venturi tube 204, and thus the enclosed pan 206, are also heated. Each of these items may be made of a thermally conductive material to enhance this process. The fuel that is within the enclosed pan 206 is vaporized by the heat, and mixes with the other fuel in the system. This fuel is eventually burned off, typically within a couple of minutes of lighting the stove.

The embodiment of the stove 200 shown in FIG. 11 is a very efficient model for starting. When used with the fuel tip 50, a user may experience very fast lighting of the stove 200 without having to do anything but pump a fuel bottle, turn on the gas, and light the stove. The stove should be ready for use within a minute or two.

The enclosed pan 206 may be positioned in a location that is different from the position shown in FIG. 11, but is located in the fuel line between the fuel tank 26 and the burner 210 so that it may capture excess fuel in the line but let the proper fuel-air mixture through to the burner. In an embodiment, the enclosed pan 206 is heated by the burner during combustion so that liquid fuel trapped in the enclosed pan 206 may be more quickly vaporized. As an example, the burner may be thermally connected to the enclosed pan 206 so as to heat the pan through conduction, as shown in FIG. 11, but the enclosed pan may be alternatively be heated through radiation.

Primary heat to the enclosed pan 206 is provided via the generator 202. The hot gases flowing from the generator 202 aid in vaporization of the fuel in the enclosed pan 202. Vaporization is slowed a little because the enclosed pan is attached to a number of metal parts, such as the legs for the stove 200, which dissipate heat. In an embodiment, a highly thermally conductive pan (not shown) may be arranged in the enclosed pan. The highly conductive pan would heat faster than the enclosed pan 206 because the increased thermal conductively would cause that part to heat before dissipating heat to other parts of the stove 200.

In addition, although called an “enclosed pan” herein, any structure that is capable of capturing excess fuel in the fuel line between the fuel tank 26 and the burner 210 may be used. In an embodiment, the structure is enclosed so that fuel and air flows to the burner without escaping.

The arrangement of the stove 200 shown in FIG. 11 may be used in a stove having two burners. Similar to the embodiment shown in FIG. 9, such a stove would benefit from use of the fuel tip 50, and would provide an easy-to-light stove that can maintain one or two flames via the operation of the fuel tip 50.

Other variations are within the spirit of the present invention. Thus, while the invention is susceptible to various modifications and alternative constructions, a certain illustrated embodiment thereof is shown in the drawings and has been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims.

All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

Preferred embodiments of this invention are described herein, including the best mode known to the inventor for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. 

1. A stove, comprising: a burner for providing combustion; a fuel canister, the fuel canister including liquid fuel and pressurized gas therein; a fuel conduit extending between the burner and the fuel canister; and a fuel tip within the fuel canister and being in fluid communication with the pressurized gas, the liquid fuel, and the fuel conduit, the fuel tip being arranged and configured to automatically provide a first mixture of the liquid fuel and the pressurized gas through the fuel conduit to the burner responsive to back pressure in the fuel conduit exceeding a particular pressure, and to automatically provide a second mixture of the liquid fuel and the pressurized gas through the fuel conduit to the burner responsive to back pressure in the fuel conduit not exceeding the particular pressure, the first mixture having a leaner fuel mixture than the second mixture.
 2. The stove of claim 1, comprising at least two burners.
 3. The stove of claim 1, wherein the pressurized gas is pressurized air.
 4. The stove of claim 1, wherein the fuel tip comprises a device for adjusting fuel flow into the fuel tip, the device being configured so that more fuel flows into the fuel tip when the back pressure in the fuel line exceeds the particular pressure.
 5. The stove of claim 1, wherein the fuel tip comprises a piston, the piston being arranged such that movement of the piston between first and second positions reduces fuel flow into the fuel tip.
 6. The stove of claim 5, wherein the pressurized gas is in fluid communication with one side of the piston and biases the piston toward the second position.
 7. The stove of claim 6, wherein the fuel line is in fluid communication with an opposite side of the piston such that back pressure in the fuel line biases the piston toward the first position.
 8. The stove of claim 7, further comprising a spring for biasing the piston towards the first position.
 9. The stove of claim 1, wherein the particular pressure is variable depending upon the pressure of the pressurized gas.
 10. The stove of claim 1, wherein the burner comprises: a burner top; and a burner bottom having a trough therein for capturing excess fuel during starting of the burner.
 11. The stove of claim 10, further comprising: a fuel entry from through the burner bottom; and an downturned lip on the burner top surrounding the fuel entry, the downturned lip being arranged to direct fuel that enters through the fuel entry and engages the burner top to flow along the downturned lip toward the trough.
 12. The stove of claim 1, further comprising: a structure that is capable of capturing excess fuel in the fuel line between the fuel canister and the burner.
 13. The stove of claim 12, wherein the structure comprises an enclosed structure.
 14. The stove of claim 13, wherein the structure comprises an enclosed pan spaced from the bottom of the burner.
 15. The stove of claim 14, wherein the enclosed pan is heated by a flame in the burner.
 16. The stove of claim 15, wherein heating of the enclosed pan by the flame comprises conduction between the enclosed pan and the burner.
 17. A stove, comprising: a burner for providing combustion, the burner comprising: a burner top; a burner bottom having a trough therein for capturing excess fuel during starting of the burner. a fuel canister, the fuel canister including liquid fuel and pressurized gas therein; and a fuel conduit extending between the burner and the fuel canister.
 18. The stove of claim 17, further comprising: a fuel entry from the fuel conduit through the burner bottom; and a downturned lip on the burner top surrounding the fuel entry, the downturned lip being arranged to direct fuel that enters through the fuel entry and engages the burner top to flow along the downturned lip toward the trough.
 19. A stove, comprising: a burner for providing combustion; a fuel canister, the fuel canister including liquid fuel and pressurized gas therein; a fuel conduit extending between the burner and the fuel canister; and an enclosed pan spaced from the bottom of the burner that is capable of capturing excess fuel in the fuel line between the fuel canister and the burner.
 20. The stove of claim 19, wherein the enclosed pan is heated by a flame in the burner.
 21. The stove of claim 19, wherein heating of the enclosed pan by the flame comprises conduction between the enclosed pan and the burner. 